Physical Fitness Improves Brain Health
Copyright 2006 Simon Evans Everyone knows that exercise is good for them. It contributes to weight loss and weight management. It’s good for your heart and your cardiovascular system. And it generally keeps you fit and healthier. But did you know that exercise is also good for your brain? It can actually make you smarter. Not only that, but exercise can help prevent disorders like Alzheimer’s disease, Parkinson’s disease and depression.
It can even increase your chances of recovering from a stroke or traumatic brain injury. Exercise improves learning and memory. It turns out that physical activity actually turns on hormonal support systems in your brain. The activation of these systems strengthens brain circuits that you already have and helps you develop new ones. Exercise causes a rise in several growth factors in the brain that are responsible for helping brain cells survive and divide into new brain cells, or neurons.
Only a couple of brain regions can produce new neurons and exercise increases the amount and rate of neuron production in these regions. Exercise also increases the blood supply in the brain. In laboratory studies, exercise increased the number of blood vessels that supply several brain regions. This has the effect of improving nutrient delivery and waste removal from critical regions that effect mental function. One of the brain areas producing new neurons is the hippocampus. The hippocampus plays a critical role in learning, memory and attention. Exercise induces new neuron growth in the hippocampus and improves performance on several types of cognitive tasks. Exercise improves mental health. Another important role of the hippocampus is in the response to stress. In fact, studies show that war veterans with post-traumatic stress disorder have a smaller hippocampus.
Stress actually damages the hippocampus and can cause neurons to die, the opposite of what happens when you exercise. Folks that exercise regularly know that they are much more capable of handling stress throughout their day than they are when they don’t exercise. This is, in part, because exercise and stress have opposite effects on the hippocampus and exercise improves your ‘buffer’ to handle the stress. Interestingly, anti-depressants work in a similar manner. Although, we don’t completely understand the exact mechanism of anti-depressant action, we do know that several classes of anti-depressants increase new neurons in the hippocampus. They do the same thing that exercise does! Anti-depressant drugs activate the same growth factor systems in the brain that exercise activates. They also induce new neuron growth in the hippocampus, similar to exercise routines. Psychiatrists have known for a long time that patients experiencing depression respond much better to therapy if they combine it with regular exercise. In some cases, exercise alone is sufficient to alleviate depressive symptoms. With so many kids and adults on anti-depressants today, I have to wonder what proportion of them could get off these medications with more physical activity.
Of course, anti-depressant therapy is both beneficial and necessary for some folks. But the rate of prescriptions today, especially in kids, is out of control. Exercise protects the brain from damage and disease. Studies also show that exercise protects the brain from aging and injury. Older adults that regularly exercise perform better in cognitive tasks and have lower rates of Alzheimer’s and Parkinson’s disease. They also recover stronger from strokes and from accidental brain injury. One can argue that people that exercise have many factors in their lives that can contribute to these findings. For example, they smoke less, eat better, etc. However, studies in laboratory animals also support the idea that exercise is protective. Animals that are exercised are protected against traumatic brain injury in laboratory tests and don’t develop the extent of Alzheimer’s and Parkinson’s disease in model systems.
Studies also show that in addition to exercise’s protective role, it is a valuable therapeutic tool for brain function. Fitness training improves cognitive functions relative to planning, scheduling, task coordination and attention. Adults that exercise have more grey matter, representing more brain cells, than adults that don’t exercise. Focus on the young family. All of the beneficial effects of exercise are compounded by starting early in life. It’s kind of like compound interest in the bank. The earlier you start saving, the more money there is to earn interest in the end. Yet, unfortunately, schools are cutting physical education for budgetary reasons. Soccer moms must unite and get exercise back in our schools.